The present invention relates generally to fluid power devices and more particularly to a wave rotor apparatus.
It is known to use an axial wave rotor as a supercharger in internal combustion engines for automotive vehicles. This conventional device is described in P. Akbari and N. Müller, “Gas Dynamic Design Analyses of Charging Zone for Reverse-Flow Pressure Wave Superchargers,” ICES 2003-690, ASME (May 11-14, 2003). Wave rotors have also been proposed for use in propulsive jet engines and power turbines as disclosed in U.S. Pat. No. 6,584,764 entitled “Propulsion Module” which issued to Baker on Jul. 1, 2003; and U.S. Pat. No. 5,894,719 entitled “Method and Apparatus for Cold Gas Reinjection in Through-Flow and Reverse-Flow Wave Rotors” which issued to Nalim et al. on Apr. 20, 1999; both of which are incorporated by reference herein. Various attempts have also been made to cancel an expansion wave generated by a wave rotor. Such a configuration is taught in U.S. Pat. No. 5,267,432 entitled “System and Method for Cancelling Expansion Waves in a Wave Rotor” which issued to Paxson on Dec. 7, 1993, and is incorporated by reference herein. Traditional attempts to use depressions or pockets to control wave reflections of off-design operation undesirably, reduce the sensitivity of axial wave rotors to engine speed changes. Nevertheless, there still exists a need to improve the performance and reduce the size of traditional wave rotors to enhance their commercial viability or adapt a different geometry for more convenient implementation.